U.S. Pat. No. 5,488,211 entitled "A Latching Arrangement for High Ampere-rated Circuit Breaker Operating Springs" describes a combined bell alarm and lock-out accessory that is connected with the electronic trip unit that controls a high ampere rated circuit breaker. The accessory interacts with the circuit breaker operating mechanism to activate the bell alarm upon circuit interruption and to prevent the closing of the circuit breaker contacts until the accessory is manually reset. U.S. patent application Ser. No. 08/248,900 filed May 25, 1994 entitled "Accessory Compartment for High Ampere-rated Circuit Breaker" relates to a high ampere-rated circuit breaker that meets the electrical code requirements of the world market. The circuit breaker electronic trip unit is contained within a recess in the circuit breaker cover and is interlocked with the circuit breaker operating mechanism to articulate the operating mechanism upon removal. The accessory units are contained within an adjoining accessory compartment recess within the circuit breaker cover.
U.S. patent application Ser. No. 08/248910 filed May 25, 1994 "Bell Alarm and Lock-out for High Ampere-rated Circuit Breakers" describes a combined bell alarm and lock-out accessory that is connected with the electronic trip unit that controls a high ampere rated circuit breaker. The accessory interacts with the circuit breaker operating mechanism to activate the bell alarm upon circuit interruption and to prevent the closing of the circuit breaker contacts until the accessory is manually reset.
U.S. patent application Ser. No. 08/266,409 filed Jun. 27, 1994 entitled "Interlock Arrangement for High Ampere-rated Circuit Breaker Operating Springs" relates to a high ampere-rated circuit breaker which meets the electrical code requirements of the world market.
The charging of the powerful operating springs controlling the circuit breaker contacts is made manually by means of a ratchet and pawl assembly. A two stage latching arrangement controls the retention and release of the pawl to retain and discharge the operating springs. The latches are interlocked with the operating springs drive shaft to prevent the discharge of the operating springs when the contacts are in the closed condition.
When such accessories as described above are used within industrial applications, and have to be reset to insure future operation, it is desirable to insure that the associated circuit breaker contact closing springs are capable of being immediately reset. However, it is important that the circuit breaker contacts are not closed to turn on the circuit breaker unless and until the accessory has become reset and operational.
An early use of accessories within high ampere-rated circuit breakers is described within U.S. Pat. No. 4,001,739 entitled "Circuit Breaker with Bell Alarm and Breaker Lockout Accessory." The circuit breaker contacts are interlocked with the accessories by insuring that the circuit breaker contact springs cannot be reset until the associated accessory is reset, i.e. becomes operational.
The present invention improves over the early lockout accessory arrangement by allowing the circuit breaker operating mechanism to be reset independently from the accessory while still deterring closing of the circuit breaker contacts until and unless the accessory itself has become operational.
One purpose of the instant invention is to describe a circuit breaker lock-out mechanism that interacts with the circuit breaker operating mechanism to disable the circuit breaker operating mechanism to prevent the circuit breaker contacts from being closed until and unless the associated accessory becomes reset.